As is known in the art, emerging technology and increasing demand for large-scale high-speed data communications have made it important for systems to achieve efficient and reliable digital data transmission and storage. In particular, an important goal for many wireless network protocols is high throughput. In communication networks, throughput (also sometimes referred to as “network throughput”) may be defined as the average rate of successful message delivery over a communication channel.
As is also known, channel conditions affect network throughput. Many factors degrade channel quality, including signal attenuation, noise, interference, and multipath fading. Wireless channels vary with time, sometimes even at time-scales shorter than a packet time. Thus, to achieve high throughput, a protocol must not only operate at the best rate given a set of channel conditions but must also adapt to variations.
These problems are well-known, fundamental ones. Current wireless networks, including IEEE Standard 802.11 (Wi-Fi) and various wide-area cellular wireless standards, address them by providing a large number of physical layer (PHY) mechanisms, including a variety of channel codes, various parameters for these codes, and several modulations. The link and subnetwork layers implement policies to dynamically select and configure the discrete choices and parameters provided by the PHY. In 802.11 networks, for instance, this choice is generally made by a bit rate adaptation protocol by observing channel conditions, such as the signal-to-noise ratio (SNR), interference-free bit error rate, dispersion in the constellation space, frame loss rate, or the time taken to successfully transmit a frame.